1. Field of Invention
The present invention relates to a building structure connecting member, and more particularly to a semi-butterfly connecting clamp and a building steel framework joint structure.
2. Description of Related Arts
In building steel framework structures, the connection quality between the vertical column and the cross beam is the key to structural-load-bearing capacity and seismic resistant capability. The connection of conventional steel structure joint is generally formed by butt welding or welding connection combined with bolts. However, these methods have disadvantages in that there may be bad stress transmitting, stress concentration, greater probability of partial damage, mechanical property dependent on the material quality and wall thickness of the column, and low economical performance.
Chinese patent application No. 200510103007.7 discloses a butterfly-type self-locking connecting clamp with friction shear resisting plate and a building steel framework joint structure. As shown in FIGS. 1A and 1B, a schematic view of an existing butterfly self-locking connecting clamp structure and an isometric view of a corresponding building steel framework joint structure are provided, respectively. The building steel framework joint structure comprises a vertical column 1′, a cross beam 2′, four connecting clamps 3′ and four friction shear resistant plates 11′. As shown in FIG. 1A, each of the connecting clamps 3′ comprises a clamp main body 4′. Four clamp wings 5′ are provided at two ends of the clamp main body 4′, respectively, wherein each of the clamp wings 5′ comprises a bearing plate 7′ connected to the clamp main body 4′, a pre-tightening plate 6′ opposite to the bearing plate 7′, and a self-locking fastening plate 9′ connecting the bearing plate 7′ with the pre-tightening plate 6′, in which, the pre-tightening plate 6′ and the self-locking fastening plate 9′ are integrally formed. The self-locking fastening plate 9′ has two through holes, and the pre-tightening plate 6′ has one through hole. A projecting self-locking shoulder 8′ is provided at an end of the self-locking fastening plate 9′ near the clamp main body 4′, an arc recess is provided between one end of the self-locking shoulder 8′ and the clamp main body 4′, and an inclined surface is provided between the other end of the self-locking shoulder 8′ and the pre-tightening plate 6′. As shown in FIG. 1B, the clamp main body 4′ is located on a side surface of the vertical column 1′, two pre-tightening plates 6′ are positioned opposite to each other, a web plate of the cross beam 2′ is inserted between the two pre-tightening plates 6′ opposite to each other, upper and lower flange plates of the cross beam 2′ are arranged above and below the self-locking fastening plates 9′, respectively. The two pre-tightening plates 6′ are firstly fixed and connected to the web plate of the cross beam 2′ by screws, and then the self-locking fastening plates 9′ are connected with the upper and lower flange plates of the cross beam 2′ by screws. The four friction shear resistant plates 11′ are distributed evenly between the vertical column 1′ and the cross beam 2′. Each of the friction shear resistant plate 11′ is formed by a V-shaped friction plate 111′ and a shear resistant plate 112′, in which the friction plate 111′ thereof is attached to an external surface of the vertical column 1′, the shear resistant plates 112′ of adjacent friction shear resistant plates and the web plate of the cross beam 2′ therebetween are fixed together by bolts, and each shear resistant plate 112′ is located below the cross beam 2′. The distance between the external surfaces of the two parallel upper and lower self-locking fastening plates 9′ of the connecting clamp 3′ may be determined according to the height of the cross beam 2′ to be mounted, and the distance between the self-locking shoulder 8′ at one end of the clamp main body 4′ and that at the other end thereof in the same plane is determined according to the width of the vertical column 1′ to be assembled. However, the connection structure of this building steel framework joint has its disadvantages in that: the distance between the parallel upper and lower self-locking fastening plates 9′ must be fitted with the height of the web plate of the connected cross beam 2′ for the connecting clamp's integrally design, otherwise, they will be hard to be connected together. As a result, there is the need to measure accurately their positions while designing, and the designed connecting clamp 3′ only can be suitable to a single height cross beam 2′. Therefore, it is inconvenient to adjust the connection joint of the building steel framework joint. When the two self-locking shoulders 8′ of the connecting clamp retains the friction shear resistant plates 11′ on the outside surface of the vertical column 1′ of the building steel framework, since the self-locking shoulder 8′ is designed in a fixed form, the distance between its friction shear resistant plates 11′ for retaining the outside surface of the vertical column 1′ can not be adjusted. Hence, the retaining width of the self-locking shoulder 8′ of the connection clamp must have been precisely calculated when producing, otherwise it is difficult to connect them to the friction shear resistant plates 11′ of the vertical column 1′. On the other hand, when a strong outside force is applied on the building steel framework structure, for example, earthquake, the action between each of the prior connecting clamps 3′ and each of the friction shear resistant plates 11′ outside of the vertical column is a rigid action, all of the energy produced in this condition will be applied onto the vertical column 1′, and thus it is easily to break the building steel framework joint structure. In order to overcome the above disadvantages in the prior art, the present applicant had made various improvements, and successively filed a series of patent applications. The present application is a continuation application of the above applications.